The first question to address, regarding last week's UK election result, is how long Theresa May's minority government can last.
This has an urgent bearing at Stormont, where talks to restore devolution are due to restart today and a deal by the autumn had been widely expected.
Neither Sinn Féin nor the DUP can risk negotiation and compromise if they might have to go back on the campaign trail at any moment.
I had a chance to speak to unionist and republican representatives as the results came in. Their first instinct was that May would be gone by the morning, another election was inevitable and Stormont talks would have to be put on ice.
Things look different now the prime minister has survived the weekend and cobbled together a deal with the DUP.
While the arrangement is obviously fragile, the Tories have little choice but to try and make it durable. They will not trigger an election that Jeremy Corbyn’s Labour might win – suddenly a realistic prospect.
They will even struggle to rid themselves of May. Rightly or wrongly, the British public expects prime ministers to have a personal mandate. A minority government with an “unelected” head looks untenable.
Dependence on a handful of Northern Ireland MPs can in contrast be surprisingly tenable. One SDLP MP propped up a Labour government through the last half of the 1970s, before bringing it down in a no-confidence motion.
The DUP’s 10 MPs are a solid support by comparison, giving the Conservatives a working majority of seven.
Plausible
So no election for several years is plausible and the autumn timetable for restoring Stormont once again looks doable. The DUP unquestionably remains desperate to get back into office in Belfast. Power in London is glorious but fleeting, as it knows.
Speaking to the BBC on Saturday, former DUP assembly member Alasdair Ross estimated the confidence-and-supply arrangement could last for 18-24 months.
On balance, Sinn Féin is more likely to return to Stormont due to the election.
Its own superb showing, almost doubling its MPs to seven, reflects a mixed message from its electorate.
Boycotting Stormont and Westminster could make Gerry Adams's party look completely self-indulgent
Voters rewarded Sinn Féin for walking out of Stormont and standing up to what they saw as DUP arrogance, yet it is striking how many of these voters speak of the need to bring Stormont back. They expect Sinn Féin to make use of the strength they have given it.
Normally, they would not expect that strength to be deployed at Westminster. Sinn Féin campaigns on a proudly abstentionist ticket, although this often feels like IRA decommissioning – a “not-an-inch” issue whose sudden abandonment would surprise and upset nobody.
The matter has never been forced because the party’s numbers in the Commons have never been decisive. That has now changed – the Tory-DUP alliance would need to lose only three MPs before Sinn Féin’s attendance could swing a no-confidence motion. Typical rates of death and defection suggest this point will arrive within two years.
In the meantime, Sinn Féin will be crucified over every Commons vote in which it could have made a difference, of which there will be many, given the difficulties of whipping 318 Tory MPs through the Brexit process.
Boycotting Stormont and Westminster during this would make Gerry Adams’s party look completely self-indulgent.
Reining in the arrogance
A republican return to Stormont will still depend on the DUP reining in the arrogance that so antagonised Sinn Féin’s voters. Any sign of unionists using their new Westminster power in Stormont negotiations, or against nationalist interests in general, would be disastrous.
DUP figures have given plenty of indication they recognise this danger. That does not mean they will be able to resist it. Being catapulted from the doldrums to the top of UK politics would go to any party’s head.
The DUP is most likely to use its power to ask for cash and favours for Northern Ireland, most of which will require a devolved executive to administer. Sinn Féin will not want to be seen to block this, especially as the DUP seems focused on reversing benefit cuts.
May’s weakened position plus the DUP’s special requirements from Brexit have major implications for the whole of Ireland. Northern Ireland’s unique reliance on the agrifood sector means the DUP wants a far softer Brexit than even it may realise.
Delightfully, it could end up being instrumental in keeping the UK inside the customs union, while Sinn Féin will have all its complaints about the Border addressed, much to its disappointment.
Since the election, remarkable levels of ignorance and hostility towards unionists have been revealed among the English left and the London media.
Unionists are unlikely to be bothered by this – the need to be liked is an Irish weakness. However, they should be concerned by the long-term implications.
Propping up the Tories could make Ulster unionism a culturally unacceptable practice among the Corbyn generation – two-thirds of voters under 34 backed Labour.
Just as the threat to the union from Scotland recedes, a new one is arising in England.